Optogenetics research to fight the sight-deteriorating disease retinitis pigmentosa has received more than $384,269 from the National Institutes of Health (NIH). Dr. Samarendra Mohanty, assistant professor of physics at the University of Texas at Arlington, and Dr. Digant Dave, associate professor of bioengineering, will receive the funds over the next two years from the NIH’s National Institute of Neurological Disorders and Stroke. In the past, genes used in optogenetics have been delivered to cells by virus, which can cause unwanted immune responses. Mohanty has developed a technique using a laser to create a transient submicrometer-sized hole, which allows for the gene encoding the proteins to permeate through the cell membrane. It can limit the risk of immune response as well as deliver larger genes than viral methods, he said. Samarendra Mohanty. Courtesy of UT Arlington. “Our minimally invasive near-infrared method can deliver DNA and other impermeable molecules effectively where you want it and only where you want it,” Mohanty said. “For example, in retinitis pigmentosa, only peripheral retina begins to lose light sensitivity due to loss of photoreceptors. This is where a laser can deliver the genes, making those neurons respond to light again. With a virus, the genes will be delivered everywhere, causing complications in areas already working fine.” Mohanty’s group also is researching ways that optogenetics could be used to understand how the brain works or to intervene in case of neurological disorders or to affect behavior. The goal is to create optical control and monitoring of cell activity, so the researchers also will work on refining methods for stimulating neural activity using near-IR and visible light. Mohanty’s lab at UT Arlington also will use a label-free method called phase-sensitive interferometry to monitor the changes in neurons that result from the activation by light.